As discussed in this thread at PrimeGrid: http://primegrid.com/forum_thread.php?id=2721

PrimeGrid will be suspending SoB/PSP combined sieving, this means if people want to continue sieving then they will need to use the manual reservation system at http://www.sierpinskisieve.com - my question is, should we not also be considering suspending sieving and instead focus on PRP?